1. Field of the Invention
This invention relates to a packaged assembly of orthodontic appliances that are used in the patient's oral cavity during the course of orthodontic treatment. More particularly, the present invention relates to an assembly of orthodontic appliances having a quantity of adhesive that has been applied to the base of each appliance by the manufacturer.
2. Description of the Related Art
Orthodontic treatment involves movement of malpositioned teeth to orthodontically correct positions. Tiny orthodontic appliances known as brackets are connected to exterior surfaces of the patient's teeth, and an archwire is placed in a slot of each bracket. The archwire forms a track to guide movement of the teeth to desired positions for correct occlusion. End sections of the archwire are often received in appliances known as buccal tubes that are fixed to the patient's molar teeth. In recent years it has become common practice to use adhesives to bond orthodontic appliances to the surface of the tooth, using either direct or indirect methods.
For many years, it was common practice to apply orthodontic adhesive to the base of the appliance immediately before the appliance was placed on the tooth. In some instances, a quantity of adhesive was dispensed onto a mixing pad or dispensing well, and a small spatula or other hand instrument was then used to apply a small dab of adhesive to each appliance. In other instances, a quantity of adhesive was dispensed from a syringe directly onto the base of the appliance.
Adhesive precoated brackets are known and offer significant advantages to the orthodontist. Adhesive precoated brackets have a bonding base upon which the manufacturer may apply a precise quantity of adhesive such as a photocurable adhesive. In direct bonding methods, when it is desired to mount the bracket on a tooth, the bracket is simply removed from the package and placed directly onto the tooth. For indirect bonding methods, brackets are removed from the package and placed, for example, on a replica plaster or “stone” model of the patient's dental arch to provide a custom base for later mounting on the patient's tooth, commonly using a transfer tray.
In addition to good handling properties and adequate adhesion, practitioners often desire that photocurable adhesives provide other desirable functional properties, including, for example, sustained fluoride release. In many applications, it is also desirable that the adhesive have adequate hydrophilicity or moisture tolerance, as indicated, for example, by the ability of the adhesive to absorb water or saliva, and/or the ability to provide an adequate bond under moist conditions.
Adhesive precoated brackets are typically packaged in containers that protect the adhesive from light, moisture and contaminants. Known containers include containers that receive only a single bracket. Optionally, the containers are received in a holder that is constructed for a single patient, and the holder carries a sufficient number of containers with their contained appliance for all or substantially all of the patient's teeth that are undergoing orthodontic treatment.
Over the years, many attempts have been made to improve bonding materials for orthodontic appliances to help ensure that the appliances do not unintentionally detach from the teeth. If, for example, an appliance debonds from the tooth during the course of treatment, the patient must return to the practitioner's office for reattachment or replacement of the appliance so that treatment can resume. Obviously, such occurrences represent a nuisance for both the practitioner and the patient, and may also increase the treatment cost as well as the length of time needed for treatment.